1. Field of the Invention
The present invention relates to an optical scanning frequency doubling method and an apparatus adopting the same.
2. Description of the Related Art
As demand for improved multimedia increases, the need for large display screens with high definition also increases. In addition to high resolution, realization of natural color has also become important.
To represent a prefect natural color, it is necessary to use a light source with the same color purity as a laser. One example of a device for realizing such quality is a laser projection system using a scanner.
Among conventional scanning laser projection devices, laser projection systems using a rotating polygon mirror or a galvanometer system are in highest demand. However, optical scanning devices using rotating polygon mirrors or galvanometers are expensive and difficult to miniaturize.
To overcome these disadvantages, next generation laser projection systems under development include a MicroElectro Mechanical Systems (MEMS) scanner. U.S. patent application Ser. No. 09/848,332 discloses a laser projection system using two MEMS scanners that can replace a laser projection system using a rotating polygon mirror or galvanometer.
To apply an MEMS scanner to a large screen-high resolution projection system, it is necessary to provide a sufficient scanning speed and scanning angle. However, various MEMS scanners that have been developed thus far cannot provide these features.